diff options
| -rw-r--r-- | crypto/asymmetric_keys/x509_cert_parser.c | 28 | ||||
| -rw-r--r-- | include/crypto/public_key.h | 2 |
2 files changed, 30 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c index 77547d4bd94dd..0a7049b470c18 100644 --- a/crypto/asymmetric_keys/x509_cert_parser.c +++ b/crypto/asymmetric_keys/x509_cert_parser.c @@ -579,6 +579,34 @@ int x509_process_extension(void *context, size_t hdrlen, return 0; } + if (ctx->last_oid == OID_keyUsage) { + /* + * Get hold of the keyUsage bit string + * v[1] is the encoding size + * (Expect either 0x02 or 0x03, making it 1 or 2 bytes) + * v[2] is the number of unused bits in the bit string + * (If >= 3 keyCertSign is missing when v[1] = 0x02) + * v[3] and possibly v[4] contain the bit string + * + * From RFC 5280 4.2.1.3: + * 0x04 is where keyCertSign lands in this bit string + * 0x80 is where digitalSignature lands in this bit string + */ + if (v[0] != ASN1_BTS) + return -EBADMSG; + if (vlen < 4) + return -EBADMSG; + if (v[2] >= 8) + return -EBADMSG; + if (v[3] & 0x80) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_DIGITALSIG; + if (v[1] == 0x02 && v[2] <= 2 && (v[3] & 0x04)) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_KEYCERTSIGN; + else if (vlen > 4 && v[1] == 0x03 && (v[3] & 0x04)) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_KEYCERTSIGN; + return 0; + } + if (ctx->last_oid == OID_authorityKeyIdentifier) { /* Get hold of the CA key fingerprint */ ctx->raw_akid = v; diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h index c401762850f20..03c3fb990d59c 100644 --- a/include/crypto/public_key.h +++ b/include/crypto/public_key.h @@ -30,6 +30,8 @@ struct public_key { const char *pkey_algo; unsigned long key_eflags; /* key extension flags */ #define KEY_EFLAG_CA 0 /* set if the CA basic constraints is set */ +#define KEY_EFLAG_DIGITALSIG 1 /* set if the digitalSignature usage is set */ +#define KEY_EFLAG_KEYCERTSIGN 2 /* set if the keyCertSign usage is set */ }; extern void public_key_free(struct public_key *key); |